The present invention relates to heat-cross-linking type water-soluble coating materials obtained by converting copolymers having a carboxyl group, a hydroxyl group and a tertiary aliphatic group into amine salts to render the same soluble in water and combining said amine salts with water-soluble amino resins.
Processes for producing copolymers of .alpha.,.beta.-ethylenically unsaturated carboxylic acids, such as acrylic acid or methacrylic acid, and polymerizable unsaturated polymers, and water-soluble salts thereof, are well known.